Following the opening credits appear the words "Once upon a time." The first scene shows two masculine hands sharpening a razor. After the man has tested the sharpness of the razor he steps out on to the balcony, leans on the railing, and looks up to the sky. Presumably, he is watching the moon. There is another shot of the man looking thoughtfully to the moon and smoking before we see the face of a young woman. One of the man's hands opens her left eye while the other holds the razor. There is another shot of the moon before the final shot of an extreme close-up with the razor slicing through the woman's eye as jell-like fluids come seeping out of from behind the incision.

Buñuel explained that the eyeball sliced in the opening scene is a cow's eye which was placed into an open eye socket of an actress missing her original eye. However, a close inspection of the shot makes it clear that it is in fact a cow's eye in a cow's socket.